214 



Fishery Bulletin 103(1) 



phausiid density. Similar to our findings, the estimates 

 of larval crab densities from Rogers et al.'s and Kendall 

 et al.'s studies were always highest in bays. In autumn. 



18 



16 

 14 



12 

 10 



all locations 



Chiniak Bay 



Ugak Bay 



Kiliuda Bay 



Shelf 



50 75 100 



Standard length (mm) 



125 



B 



80 100 120 140 



Age (d) 



c 



160 180 



^ 



k.' * 



•*, 



20 40 60 80 



Standard length (mm) 



100 



Figure 5 



Least-squares regressions of age-0 walleye pollock 

 tTheragra chalcogramma) length on weight (Al, length 

 on age (B), and gut content weight on length (C) for 

 individuals collected from four areas off east Kodiak 

 Island, 5-18 September 1993. 



the larger zooplankters are of principal importance to 

 age-0 pollock because of size-related changes in diet 

 (Table 5A, Merati and Brodeur, 1996). 



By all accounts, age-0 pollock collected from Chiniak 

 Bay fared as well or better than individuals in each of 

 the other areas sampled. Wilson (2000) found that the 

 density of age-0 pollock in the Chiniak Bay vicinity 

 predicted Gulf-wide recruitment. However, these fish 

 represent a minuscule part of the Gulf-wide population 

 of age-0 pollock. Even if two cohorts, from spring- and 

 summer-spawnings, were produced, it seems unreason- 

 able to expect that local production would dramati- 

 cally affect gulf-wide recruitment. Alternatively, the 

 abundance and condition of age-0 pollock in this vicin- 

 ity might reflect larger-scale processes that relate to 

 gulf-wide recruitment. Identifying large-scale processes 

 based on small-scale sampling, however, is complicated 

 by variation at high spatial and temporal frequencies. 

 For example, the relatively high density of pea crab 

 (Fabia subquadrata) megalopae in combination with 

 influxes of freshwater (Epifanio, 1988) indicate that 

 local dynamics are important in sustaining prey popu- 

 lations in Ugak and Kiliuda bays. In contrast, Chiniak 

 Bay might be more affected by influxes of oceanic prey. 

 Such influxes could be facilitated by cross-shelf sea val- 

 leys, which extend into all the fjords that we sampled. 

 Indeed, Kendall et al., 2 Lagerloef (1983), and Stabeno et 

 al. (2004) have all shown that the local sea valleys in- 

 duce cross-shelf flow in the ACC. Furthermore, Inzce et 

 al. (1997) found that zooplankton density was elevated 

 in the Shelikof Sea Valley above the density found at 

 adjacent shelf areas; a similar phenomenon, however, 

 was not observed off northeastern Kodiak Island (Ken- 

 dall et al. 2 ). Compared to the other bays, Chiniak Bay 

 might be best positioned to receive enriched ACC water 

 that flows south from where it bifurcates at the en- 

 trance to Shelikof Strait. Such enriched water may also 

 be an important transport mechanism for immigrating 

 larval and juvenile pollock (Wilson, 2000). 



Because of the inconsistency among our various indi- 

 ces (i.e., weight-at-length, length-at-age, otolith incre- 

 ment width), it is difficult to conclude that fish over 

 the shelf and in Ugak and Kiliuda bays were prey 

 limited. Over the shelf, recent growth rates were not 

 low despite relatively small individual size and low 

 prey density. For example, the low prey densities and 

 small fish sizes over the shelf contrasted with recent 

 fish growth that was not low. Age-0 pollock are capable 

 of social foraging behavior to compensate for food scar- 

 city (Ryer and Olla, 1992), but it is unclear that the 

 associated energetic cost (Ryer and Olla, 1997) would 

 depress body weight before slowing otolith growth. In 

 contrast, fish in Kiliuda Bay had relatively slow recent 

 growth and low body weight, but age-specific length 

 was large. The observed differences in age-specific 

 length are somewhat discounted by the fact that such 

 differences may have arisen any time after hatching 

 and are not necessarily indicative of recent differences 

 in growth. Another complication was our inability to 

 reconstruct the spatial history of the sampled fish; 



